MONTERREY, México - Slovakia's power pair snapped up berths in the quarterfinals of the Monterrey Open on Thursday, with one of them having to grind it out far longer than the other one as the second round wrapped up.

Dominika Cibulkova, seeded No.4, was the first of the Slovaks to take the court and she sure had her hands full against Sara Errani, dropping the first set and winning a lengthy second set before finally going on cruise control in the third, beating the tenacious Italian in a fast finish, 36 64 61.

Daniela Hantuchova, seeded No.2, burst out of the blocks for a 61 30 lead over Kaia Kanepi and barely took her foot off the gas, prevailing, 61 63.

"I played better than I did in my first match," Hantuchova said. "I made fewer mistakes and moved well, and I'm happy with the win. It was also a completely different opponent compared to my first round, hitting very hard."

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Other winners were No.5 seed Agnes Szavay, who beat Anna-Lena Groenefeld, 61 67(4) 61; and Anastasija Sevastova, who followed her first round stunner over Jelena Jankovic with a 61 62 rout of Iveta Benesova.

Friday's quarterfinals will pit Hantuchova against Vania King, No.3 seed Anastasia Pavlyuchenkova against Klara Zakopalova, Cibulkova against Szavay and Sevastova against Alizé Cornet.